Hi, I am android developer. Kotlin language not available. Kindly add it.
Since most Kotlin developers have probably long since moved to more fully-featured IDEs (can’t speak to what those are; not a Kotlin dev myself), you will probably be waiting a long time to get something made by someone else.
If you’re really determined to use Notepad++ to write Kotlin, your options would seem to be:
1a. Use the User defined language system, supplemented with EnhanceAnyLexer as needed/desired.
OR 1b. If you’re really hardcore, write a new lexer in C++ and submit it to the fine people at Lexilla
2. Maybe use NppLspClient with some Kotlin LSP server to get autocompletions and syntax analysis and whatnot?